Apparatus for notching a disc



F. P. ANFUSO 3,355,975

APPARATUS FOR NOTCHING A DISC Filed March 8, 1965 INVENTOR FEAN/f P. A/VFl/JO M BY ML mm ATTORNEY United States Patent 3,355,975 APPARATUS FOR NOTCHING A DISC Frank P. Anfuso, Bethlehem, Pa, assignor to Basic Products, Inc., Eutztown, Pa. Filed Mar. 8, 1%5, Ser. No. 437,670 2 Claims. (Cl. 835-411) ABSTRACT OF THE DISCLOSURE A punch in a guide at one end of a base is vertically reciprocated by a lever pivotally mounted to the punch and to the guide. A hub, adjustable along the base to or from the guide, permits the periphery of discs of various sizes rotatabiy mounted through central apertures therein on the hub to enter a horizontal slot in the guide and thereby underlie the punch. The disc is repeatedly notched by the punch and rotated between notches to form a sawtoothed periphery therein.

The present invention relates broadly to apparatus for making an improved sanding or abrasive disc. More specifically, the present invention relates to apparatus for imparting a particular peripheral configuration to a sanding or abrasive disc which may be made from a circular blank or from a previously peripherally worn disc.

Circular sanding or abrasive discs find wideapplication in many diverse fields, one particular field being automotive body work. Automobile have many sculptured concave curves or surfaces which the sanding disc is required to abrade when body repair work is to be done. Conventional sanding discs having a circular periphery are incapable of abrading these concave curves or surfaces without leaving arc-like gouge marks as is known to all those familiar not only with this specific art but with the use of small power tools in general. Moreover, certain paints, particularly the acrylic paints used on modern automobiles, have a pronounced tendency to gum or clog the standing disc, rendering the same ineffective, when the temperature of the work is raised due to friction, and the conventional sanding disc is notorious for its capacity to cause the work to heat up. Further, the most useful portion of the sanding disc, viz., the area of the sanding disc adjacent its periphery, is worn long before those portions inwardly thereof, and consequently conventional sanding discs are discarded before their theoretical economically useful life is reached, which can be a fairly expensive proposition for any shop using these sanding discs in large quantities.

The foregoing problems are not unique to the automotive body work field, but have risen in most other fields in which sanding discs are employed.

An object of this invention is to provide apparatu for making an improved sanding or abrasive disc from a circular blank or from a previously peripherally worn sanding disc, thus prolonging several-fold the useful life of this latter sanding or abrasive disc.

Another object of this invention is to provide simple, durable and reliable apparatus which can be operated easily and surely by an individual having no particular mechanical skill to rapidly make a properly balanced improved sanding or abrasive disc from a circular blank or from a previously peripherally worn sanding disc.

Other and further objects of this invention will become apparent during the course of the following description.

I have found that the foregoing objects can be attained by providing apparatus which comprises a central hub for rotatably mounting a sanding disc and a notcher or puncher operably upon the periphery of said sanding disc, the distance between said central hub and said notcher or puncher being adjustable to accommodate a range of disc diameters.

Referring now to the drawing, in which like numerals represent like parts in the several views:

FIGURE 1 represents a View in plan of the apparatus of the present invention, showing in phantom the sanding or abrasive disc mounted thereon and partially peripherally notched.

FIGURE 2 represents a view in side elevation of the apparatus of the present invention, showing in phantom the sanding or abrasive disc mounted thereon.

FIGURE 3 represents a view in end elevation of the apparatus of the present invention, partially broken away to show more clearly certain details of construction.

FIGURE 4 represents a vertical section taken along the line 4-4 of FIGURE 1, showing the slidable hub rotatably mounting the sanding or abrasive disc to the said apparatus, a portion of the said sanding or abrasive disc being shown in phantom.

FIGURE 5 represents a section in plan taken along the line 5-5 of FIGURE 2, showing the notcher or puncher in the guide therefor.

FIGURE 6 represents a view of the improved sanding or abrasive disc.

The improved sanding or abrasive disc 1 is seen as having a particular notched peripheral configuration (FIGURE 6) comprising peripheral sawteeth 2 having curved fillets 3 at their bases. The disc 1 has central aperture 4 by means of which the said disc 1 may be mounted on the arbor of the sander (not shown) with which the said disc 1 is to be used.

Disc 1 is made on notching or punching apparatus 5.

The notching or punching apparatus 5 comprises base 6 having a longitudinal slot 7 in the top thereof. Hub 8 is longitudinally adjustably mounted to base 6 by means of screw 9 having head it) engageable with the underside of the top of said base 6, the said screw 9 passing through longitudinal slot '7 into threading engagement with the said hub 8. It will be apparent that the position of hub 8 lengthwise of longitudinal slot 7 can be adjusted and then fixed or maintained by manually turning the hub 8 so as to draw the head iii of screw 9 securely against the underside of the top of base 6.

Guide 11 is secured to one end of base 6 and slidably receives notcher or puncher 12 for reciprocation therein. Notcher or puncher 12, as shown in FIGURE 5, has a configuration matching that of the desired notch, and is provided with spaced cars 13.

Lever 14, with operating handle 15 at one end thereof, extends between spaced cars 13 of notcher 12 and is pivotally mounted thereto by means of bolt 16 passed through the said spaced cars 13 and lever 14 and secured by nut 17.

Base 6 is provided with a pair of spaced ears adjacent guide ill, and lever 14 also extends between these spaced ears 18 and is pivotally mounted therebetween by means of bolt 19 passed through the said spaced cars 18 and lever 14 and secured by nut 20.

It will be apparent that, as operating handle 15 is raised and lowered, notcher 12 will be reciprocated up and down in guide 11.

Guide 11 is indicated in FIGURE 5 as being essentially square in plan, and it will be noted from FIGURE 2 that the two sides or faces of guide 11 facing hub 8 are cut out at 211 for practically their full horizontal dimension so as to provide in guide 11 a mouth 22 at the level of the top of base 6, into which mouth 22 the edge of the disc 1 to be notched is inserted. Also, as indicated in FIGURES 2 and 3, base 6 is provided with an opening 23 through the top thereof into which notcher 12 descends to perform its notching or punching stroke.

It will of course be understood that the hole in lever 14 through which bolt 16 is passed is slightly elongated parallel to the length of said lever 14 to provide the necessary clearances in the operation of the notching apparatus 5.

In the preferred embodiment herein shown, notcher 12 is oriented with respect to hub 8 in such manner that the two sides of notcher 12 facing said hub 8 form equal angles with reference to that line passing through the center of hub 8 and the intersection of the two said sides of notcher 12. In other words, the two sides of notcher 12 facing hub 8 are symmetrically angularly disposed about a line passing through the center of hub 8 and the intersection of the two said sides of notcher 12. In this manner, the notches formed around the periphery of disc 1 have sides which are symmetrically angularly disposed with reference to the radius passing through the root of the notch (i.e., each sawtooth is essentially an isosceles triangle). This provides a balanced tooth to the sawtoothed or notched peripheral configuration of said disc 1, which is better able to withstand the stres of the abrading or sanding operation to which the disc 1 is to be put. Even more specifically, the two sides of notcher 12 facing hub 8 form an angle of 45 with the line passing through the center of hub 8 and the intersection of the two said sides of notcher 12, so that the roots of the teeth of the sawtoothed or notched peripheral configuration are bounded by a 90 angle, the apex of the angle as hereinbefore described being curvecl fillet 3, so that each sawtooth is essentially a right isosceles triangle.

The operation of notching appartus will now be described.

Hub 8 is loosened, and hole 4 of a circular blank 24 to be notched, which circular blank 24 is indicated in phantom in FIGURES 1, 2 and 4, is placed over and around hub 8, the said hole 4 being slightly larger in diameter than that of hub 8 so as to permit rotation of circular blank 24 with respect to hub 8, and at the same time, the edge of circular blank 24 is, slipped into month 22 to the desired extent (i.e., to the extent necessary to form teeth of the desired depth), hub 8 being shifted along slot 7 to the extent required by the foregoing. Then hub 8 is manually tightened to fix its position relative to notcher 12. The operator then lowers handle to punch one notch in the periphery of circular blank 24. Thereafter, handle 15 is raised so that the bottom of notcher 12 clears the face of circular blank 24, and the operator manually rotates circular blank 24 and then lowers handle 15 to punch in circular blank 24 another notch adjacent the one previously punched, and this operation is continued around the periphery of circular blank 24 until the entire periphery thereof is provided with the desired configuration. It is a fairly simple matter to judge by eye alone the degree to which the circular blank 24 must be rotated between punches so that the notches are well formed, and by the exercises of a reasonable amount of good judgment, the last notch to be punched in the periphery of circular blank 24 can be fairly well, if not almost perfectly, formed, although malformation of this one last notch should not adversely affect the static or dynamic balance of circular blank 24.

It will be apparent that notching apparatus can handle circular blanks 24 over a wide range of diameters, due to the adjustable feature of hub 8. It will also be apparent that, because slot 7 extends toward notcher 12 and, specifically, because slot 7 when projected bisects the angle formed by those two faces of notches 12 facing hub 8, the sawteeth punched in the periphery of circular blank 24 are always perfectly oriented relative to each other and to the center of circular blank 24, regardless of the diameter of said circular blank 24-.

Although the operation of my notching apparatus 5 has been described above in connection with a circular blank 24, it will be apparent that previously peripherally worn notched disc 1 can be renotched to a smaller effective diameter, and this process can be repeated each time Cir the periphery of notched disc 1 is worn in a sanding or abrading operation, thus permitting reuse of the said disc 1 many times. While the notched disc 1, after it has been peripherally worn, can be renotched directly in notching apparatus 5 without first being trimmed to a circular shape or blank, it may be desired to first remove the worn teeth and reduce the said notched disc 1 to a new circular blank 24, and this can be done on suitable apparatus to provide a true circular shape.

The notched sanding or abrading disc 1 is placed on the arbor of a power tool in the known manner, and the face thereof may be employed in conventional fashion for sanding or abrading. When contour surfaces, particularly those which are concave, are to be followed, the notched periphery is used for this purpose, being flexible and eminently adapted to follow such curved surfaces. The sawteeth forming the notched peripehry of disc 1 generate a fastmoving current of air as the said disc 1 spins, and this current of air serves to cool the surface of the work as well as the surface of the disc, thereby preventing or mitigating gumming of paint which may be on the surface of the work, as well as to blow abraded material off and away from the surface of the work. The curved fillets 3 between adjacent sawteeth prevent or mitigate tearing of the sawteeth. A notched disc 1 of the type herein described has been found to be most useful.

While I have shown the best embodiments of my invention now known to me, I do not wish to be limited to the exact structures herein shown and described, but may include such modifications, substitutions or equivalents as are embraced within the scope of the specification, drawing and claims.

What is claimed is:

1. Apparatus for forming a saw-toothed periphery in a fiat disc having a central aperture, said apparatus comprising:

(a) an elongated base having a fiat upper surface, a

first end and a second end,

(b) a vertical guide element mounted to said base adjacent the first end thereof, said guide element having a square opening extending vertically therethrough,

(c) a square opening in the flat upper surface of said base in registry with the square opening in said guide element,

(d) one corner of said square openings lying along the longitudinal axis of said elongated base,

(e) a notching element slidably mounted in the square opening of said guide element, said notching element having a square horizontal cross-section registering with said square opening of said guide element, said notching element adapted to be reciprocated towards or selectively away from the square opening in the flat upper surface of said base,

(f) a pair of first spaced ears on top of said guide element,

(g) a pair of second spaced ears on top of said notching element,

(h) a lever having a first end and a second end, said lever passing between said first and second pairs of spaced ears with the first end of said lever overlying the first end of said base, said lever overlying the longitudinal axis of said base,

(i) first bolt means passing through said lever and said first pair of spaced ears, thereby pivotally mounting the first end of said lever to said first pair of spaced ears,

(j) second bolt means passing through said lever and said second pair of spaced ears, thereby pivotally mounting said notching element to said lever at a point between the first and second ends of said lever,

(k) a horizontally disposed slot in the lower portion of said guide element adjacent the fiat upper surface of said base, said slot extending inwardly of said guide element from that portion of the periphery of said guide element facing the second end of said base to that diagonal between opposite corners of the square opening in said guide element transverse to the longitudinal axis of said base,

(1) a hub slidably mounted to the fiat upper surface of said base and adjustable along the longitudinal axis of said base towards or selectively away from said guide element, said hub being adapted to extend through the central aperture of said disc and thereby rotatably support the said disc,

(m) whereby the edge of said disc can be placed in the horizontal slot of said guide element to underlie the notching element,

(n) and whereby the apparatus can accommodate discs of various diameters by adjustment of said hub along the longitudinal axis of said base,

(0) and whereby said lever can be actuated to pass the notching element through the periphery of the disc,

(p) and whereby the disc can be rotated about the hub after each actuation of the lever to provide a sawtoothed edge extending completely around the periphery of the disc.

2. Apparatus as in claim 1, further comprising:

(q) said base having an elongated slot formed in the flat upper surface along the longitudinal axis of said base,

(r) said hub having an internal threaded opening formed vertically therein,

(s) a screw extending through said slot, the head of said screw bearing against the underside of said flat upper surface of said base, the said screw being threaded into the internal threaded opening of said hub, thereby to hold said hub against the flat upper surface of said base.

References Cited UNITED STATES PATENTS 1,362,604 12/ 1920 Czaran 83633 X 2,363,630 11/1940 Wales 83597 2,433,117 12/ 1947 Hollander 83917 X 2,705,534 4/1955 Ingersoll 83-693 2,751,980 6/ 1956 Garver 839 17 X 3,227,025 1/ 1966 MacMillan 83581 JAMES M. MEISTER, Primary Examiner. 

1. APPARATUS FOR FORMING A SAW-TOOTHED PERIPHERY IN A FLAT DISC HAVING A CENTRAL APERTURE, SAID APPARATUS COMPRISING: (A) AN ELONGATED BASE HAVING A FLAT UPPER SURFACE, A FIRST END AND A SECOND END, (B) A VERTICAL GUIDE ELEMENT MOUNTED TO SAID BASE ADJACENT THE FIRST END THEREOF, SAID GUIDE ELEMENT HAVING A SQUARE OPENING EXTENDING VERTICALLY THERETHROUGH, (C) A SQUARE OPENING IN THE FLAT UPPER SURFACE OF SAID BASE IN REGISTRY WITH THE SQUARE OPENING IN SAID GUIDE ELEMENT, (D) ONE CORNER OF SAID SQUARE OPENINGS LYING ALONG THE LONGITUDINAL AXIS OF SAID ELONGATED BASE, (E) A NOTCHING ELEMENT SLIDABLY MOUNTED IN THE SQUARE OPENING OF SAID GUIDE ELEMENT, SAID NOTCHING ELEMENT HAVING A SQUARE HORIZONTAL CROSS-SECTION REGISTERING WITH SAID SQUARE OPENING OF SAID GUIDE ELEMENT, SAID NOTCHING ELEMENT ADAPTED TO BE RECIPROCATED TOWARDS OR SELECTIVELKY AWAY FROM THE SQUARE OPENING IN THE FLAT UPPER SURFACE OF SAID BASE, (F) A PAIR OF FIRST SPACED EARS ON TOP SAID GUIDE ELEMENT, (G) A PAIR OF SECOND SPACED EARS ON TOP OF SAID NOTCHING ELEMENT, (H) A LEVER HAVING A FIRST END AND A SECOND END, SAID LEVER PASSING BETWEEN SAID FIRST AND SECOND PAIRS OF SPACED EARS WITH THE FIRST END OF SAID LEVER OVERLYING THE FIRST END OF SAID BASE, SAID LEVER OVERLYING THE LONGITUDINAL AXIS OF SAID BASE, (I) FIRST BOLT MEANS PASSING THROUGH SAID LEVER AND SAID FIRST PAIR OF SPACED EARS, THEREBY PIVOTALLY MOUNTING THE FIRST END OF SAID LEVER TO SAID FIRST PAIR OF SPACED EARS, (J) SECOND BOLT MEANS PASSING THROUGH SAID LEVER AND SAID SECOND PAIR OF SPACED EARS, THEREBY PIVOTALLY MOUNTING SAID NOTCHING ELEMENT TO SAID LEVER AT A POINT BETWEEN THE FIRST AND SECOND ENDS OF SAID LEVER, (K) A HORIZONTALLY DISPOSED SLOT IN THE LOWER PORTION OF SAID GUIDE ELEMENT ADJACENT IN FLAT UPPER SURFACE OF SAID BASE, SAID SLOT EXTENDING INWARDLY OF SAID GUIDE ELEMENT FROM THAT PORTION OF THE PERIPHERY OF SAID GUIDE ELEMENT FACING THE SECOND END OF SAID BASE TO THAT DIAGONAL BETWEEN OPPOSITE CORNERS OF THE SQUARE OPENING IN SAID GUIDE ELEMENT TRANSVERSE TO THE LONGITUDINAL AXIS OF SAID BASE, (L) A HUB SLIDABLY MOUNTED TO THE FLAT UPPER SURFACE OF SAID BASE AND ADJUSTABLE ALONG THE LONGITUDINAL AXIS OF SAID BASE TOWARDS OR SELECTIVELY AWAY FROM SAID GUIDE ELEMENT, SAID HUB BEING ADAPTED TO EXTEND THROUGH THE CENTRAL APERTURE OF SAID DISC AND THEREBY ROTATABLY SUPPORT THE SAID DISC, (M) WHEREBY THE EDGE OF SAID DISC CAN BE PLACED IN THE HORIZONTAL SLOT OF SAID GUIDE ELEMENT TO UNDERLINE THE NOTCHING ELEMENT, (N) AND WHEREBY THE APPARATUS CAN ACCOMMODATE DISCS OF VARIOUS DIAMETERS BY ADJUSTMENT OF SAID HUB ALONG THE LONGITUDINAL AXIS OF SAID BASE, (O) AND WHEREBY SAID LEVER CAN BE ACTUATED TO PASS THE NOTHCING ELEMENT THROUGH THE PERIPHERY OF THE DISC, (P) AND WHEREBY THE DISC CAN BE ROTATED ABOUT THE HUB AFTER EACH ACTUATION OF THE LEVER TO PROVIDE A SAWTOOTHED EDGE EXTENDING COMPLETELY AROUND THE PERIPHERY OF THE DISC. 